HTTP Triggers and Bindings

[asavaritayal]

HTTP webhook triggers and HTTP output bindings will use request and response objects to represent the HTTP messaging.

Request Object

The request object has the following attributes.

Attribute	Data Type	Description
method	str	HTTP method of the request
url	str	Url of the request
headers	dict	HTTP headers sent with the request
data	dict	Form data parameters
params	dict	Query string parameters
body	bytes	Raw HTTP request body

Response Object

The response object has the following attributes.

Attribute	Data Type	Description
headers	dict	Response headers
status_code	int	HTTP response status code
content	str, bytes, dict	Contents of the response

Similar to any other binding, the HTTP request and response objects can be accessed using the name attribute from function.json.

Example - https://github.com/Azure/azure-functions-python-worker/tree/master/Samples/HttpTrigger1

[1st1]

I'm wondering if we actually want to pass Response object as an argument. It seems that Azure Java allows users to just return it, which would look like this in Python:

def main(req: Request):
    return Response(status_code=404)

There's really no requirement for us to instantiate the Response object outside of the main() function. I believe that JavaScript worker allows to simply return {status: 404} hash.

[brettcannon]

I say just return it. Pre-allocating is not worth it and feels like boilerplate overhead in the function signature to me.

[1st1]

Yep, working on a PR to implement that right now.

[asavaritayal]

What if the the HttpResponse is not bound to the method return value? Can the user still set its value in the function?

[1st1]

Yes, you can declare it as an "out" binding with a different name from $return, and it will work too.

[1st1]

Everything here is now implemented in the dev branch.